Add scripts to promote S3 artifacts from test channels to stable channels (#34274)
Summary:
Currently testing against the older release `1.4.0` with:
```
PYTORCH_S3_FROM=nightly TEST_WITHOUT_GIT_TAG=1 TEST_PYTORCH_PROMOTE_VERSION=1.4.0 scripts/release/promote/libtorch_to_s3.sh
PYTORCH_S3_FROM=nightly TEST_WITHOUT_GIT_TAG=1 TEST_PYTORCH_PROMOTE_VERSION=1.4.0 scripts/release/promote/wheel_to_s3.sh
```
These scripts can also be used for `torchvision` as well which may make the release process better there as well.
Later on this should be made into a re-usable module that can be downloaded from anywhere and used amongst all pytorch repositories.
Signed-off-by: Eli Uriegas <eliuriegas@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/34274
Test Plan: sandcastle_will_deliver
Differential Revision: D20294419
Pulled By: seemethere
fbshipit-source-id: c8c31b5c42af5096f09275166ac43d45a459d25c
